Millers CSS 20W/60

[GTS290N]

I've used this oil in my 1850 for the last couple of years or so. Engine bottom end is of unknown provenance, top end is the original, refurbished a few years ago.
I changed the oil and filter several hundred miles ago and only now is the oil starting to turn the typical oil colour, I like to have fun when driving so the engine doesn't have an easy life. Today's ambient temperatures were 25C, and when parking the car after a hot run the oil light just flickered on when revs were around 500 or so, on the clutch. Oil pump has been replaced. Oil pressure sensor has been replaced. Engine sounds great, it doesn't use oil. This oil behaves the best out of all I've tried. Thoughts anyone?

[Bradman]

I’m new to Dolly ownership, but I can share my own expereince if it helps?

I had this on a Spitfire engine that was otherwise great, and it turned out to be an ageing pressure sender on the engine falsely sounding the low pressure alarm. Do you have a spare one of those that you can swap in? If you have a pressure guage you could check the reading and share the value with others to see if they have similar values.

My 1850 is due an imminent oil change (black oil changed who knows when), but idleing at 500 rpm would be like a dream! I’ve got mine to idle at around 800 rpm now (any less and it rocks around too much due to poor tune / leaky mounts). At 500 rpm my ignition light flickers on too, but my engine is totally unknown and may not be as nice as yours...

Mike.

[GTS290N]

The sensor was replaced with no difference (doesn't mean to say the new sensor is OK) and the engine idles at 750-900 depending on how it feels. Just when balancing the clutch to park the car (500 revs) in the garage the oil light comes on when the engine is very hot. Maybe I should just give more throttle....

[TrustNo1]

. Just when balancing the clutch to park the car (500 revs) in the garage the oil light comes on when the engine is very hot. Maybe I should just give more throttle....

oil light comes on because the RPM is too low so yes more throttle to bring engine speed up = better oil pressure. if its idling at 750 without the oil light on then its fine.

[soe8m]

Isn't a w60 a bit too thick? The oil pump has to work harder to push the thicker oil into the engine. That's why you read more oil pressure or a light goes out. Trying to push a thicker oil into the same size oilholes will pressurize more before the hole but less is getting in. When you "need" a w60 to have some pressure reading or a light to go out it's a bit fooling yourself for piece of mind I guess.

Jeroen

[Mahesh]

Probably not the choice of oil for most, but I have stuck with Castrol 20/50w classic.

Idles down to 400, no oil light, (yes the oil light does work), engine feels good, so far

[GTS290N]

Isn't a w60 a bit too thick? The oil pump has to work harder to push the thicker oil into the engine. That's why you read more oil pressure or a light goes out. Trying to push a thicker oil into the same size oilholes will pressurize more before the hole but less is getting in. When you "need" a w60 to have some pressure reading or a light to go out it's a bit fooling yourself for piece of mind I guess.

Jeroen

Hmmm, food for thought....

[Galileo]

Triumph say to use 15-20W/50, think a 20W/60 is something I'd put in a tractor or something like an Austin Cambridge..!

[GTS290N]

Typing in my car reg on the Opie Oils website (10% discount for TDC members) suggests using 10W40..........

[shaunroche]

When using 20W40, my oil pressure when hot dropped to about 20 psi. Using 20W60 now means it doesn't drop below about 38psi and when cold, not above 60psi.

I spoke to Miller's in Yorkshire directly who assured me it would be a good choice for old technology engines. There's a lot of sh*te spoken about oils from keyboard warriors and Garagisti, so instead of listening to me or anyone else, just ring them up and ask them.

They're on 01484 714201

In the meantime I'll continue to use the CSS and continue to rag the arse off the car at every opportunity.

[shaunroche]

Triumph say to use 15-20W/50, think a 20W/60 is something I'd put in a tractor or something like an Austin Cambridge..!

Out of interest, how do you think the quality of oil today compares to that from 50 years ago when these engines were first cobbled together?

[soe8m]

Triumph say to use 15-20W/50, think a 20W/60 is something I'd put in a tractor or something like an Austin Cambridge..!

Out of interest, how do you think the quality of oil today compares to that from 50 years ago when these engines were first cobbled together?

Quality / viscosity. Different things

[cliftyhanger]

I have used the css 20/60 in my tr7 powered tolly for ages.
I suspect the oil is a bit thicker than a GOOD QUALITY, modern 20/50 when hot, but not a lot. However, if the car gets driven vigorously it should maintain pressure better. I understand and respect Jeroens point, it is 100% valid. But many older tech oils just don't cope well.

at 100 degrees the css 20/60 has a viscosity of 22.7, pistoneeze20/50 18.5 castrol classic 20/50 17.3 comma/halfords classic 17.2
Those figures will obviously drop when the engine is hotter, 120 degrees and I would expect the 20/60 to maintain viscosity way better, whereas the old mineral oils would start to thin. That cost me a crankshaft, me thinking a classic oil would be adequate in a 1500 toledo at Goodwood.

As an aside, John kipping used to reckon the BEST answer to keeping a 1500 alive when thrashed was mobil 1 oil. And I don't think that was available as a 20/50, or indeed any 50 weight oil. Which supports Jeroens views, the viscosity isn't an issue (as long as it doesn't fall apart!) but maintaining the integrity is key. And a modern ester synthetic will do that best. HAve also had a friend who has tried millers NT oil, reckons it is the dogs danglies and maintains viscosity very well, better than anything else he has tried in his very quick 2.5 gt6.

Please feel free to take my thoughts with a pinch of salt.... but do think about modern synthetics or decent semi synthetics. Modern oils are just better.

[Galileo]

Triumph say to use 15-20W/50, think a 20W/60 is something I'd put in a tractor or something like an Austin Cambridge..!

Out of interest, how do you think the quality of oil today compares to that from 50 years ago when these engines were first cobbled together?

Quality / viscosity. Different things

+1

Personally I do not think that the 1850/Sprint engine was 'cobbled together', I think that they were very well engineered by some very talented people. I would suggest that if you need to use a high viscosity oil to maintain pressure that you should be looking to rebuild your engine rather than mask the problem.

[Galileo]

I have used the css 20/60 in my tr7 powered tolly for ages.
I suspect the oil is a bit thicker than a GOOD QUALITY, modern 20/50 when hot, but not a lot. However, if the car gets driven vigorously it should maintain pressure better. I understand and respect Jeroens point, it is 100% valid. But many older tech oils just don't cope well.

at 100 degrees the css 20/60 has a viscosity of 22.7, pistoneeze20/50 18.5 castrol classic 20/50 17.3 comma/halfords classic 17.2
Those figures will obviously drop when the engine is hotter, 120 degrees and I would expect the 20/60 to maintain viscosity way better, whereas the old mineral oils would start to thin. That cost me a crankshaft, me thinking a classic oil would be adequate in a 1500 toledo at Goodwood.

As an aside, John kipping used to reckon the BEST answer to keeping a 1500 alive when thrashed was mobil 1 oil. And I don't think that was available as a 20/50, or indeed any 50 weight oil. Which supports Jeroens views, the viscosity isn't an issue (as long as it doesn't fall apart!) but maintaining the integrity is key. And a modern ester synthetic will do that best. HAve also had a friend who has tried millers NT oil, reckons it is the dogs danglies and maintains viscosity very well, better than anything else he has tried in his very quick 2.5 gt6.

Please feel free to take my thoughts with a pinch of salt.... but do think about modern synthetics or decent semi synthetics. Modern oils are just better.

Agreed, though the key word is synthetic, that is where the improvement in oil is found from the 1970's Castrol GTX formula, maintaining it's viscosity at temperature as well as prolonged life meaning fewer oil changes.